The present invention relates to electrical test equipment and, more particularly, to an electrical test device adapted to apply power to and perform multiple measurements upon an electrical system in the powered state.
Motor vehicles such as automobiles and trucks are becoming increasingly technologically sophisticated requiring a correspondingly more sophisticated set of test equipment for maintenance and diagnostic testing. Much of the increased complexity of motor vehicles is due in part to the increased complexity of electrical circuitry and systems incorporated therein. Troubleshooting and diagnosing problems with such electrical systems requires the use of a wide array of complex test equipment.
Such test equipment may include, for example, devices commonly referred to as multi-meters and which are configured to measure resistance, voltage, and current and more. Other diagnostic testing that is typically performed on motor vehicle electrical systems includes logic probes which measure and detect the presence and polarity of voltages as well as determining the continuity in electrical circuits. Unfortunately, such logic probes typically are incapable of measuring specific voltage levels.
Another drawback associated with prior art test equipment regards the inability to test such electrical systems in the powered state. More specifically, many existing multi-meters and logic probes are incapable of diagnosing problems with the circuitry in the operating mode such as testing electrical systems of a motor vehicle in the inoperative state. For example, certain electrical devices in the electrical system of an automobile having a non-operational engine cannot be tested in the normal operating mode. However, it may be desirable to test such devices in the operational mode in order to ascertain the specific problems that can only diagnosed when such devices are operating. For example, a fan motor of a motor vehicle may require that the engine of the vehicle is operating in order to provide current to the fan motor. Unfortunately, unless power is provided to the fan motor using a separate power source, it is impossible to test and diagnose certain problems with the fan motor.
As can be seen, there exists a need in the art for an electrical test device that is capable of providing power to an electrical system in order to test such electrical system in the active or powered state. Furthermore, there exists a need in the art for an electrical test device that combines other test features such as logic probe diagnostic testing into a single unit. In addition, there exists a need in the art for an electrical test device capable of combining key measurement functions into a single instrument in order to the accelerate diagnosis of electrical problems. Finally, there exists a need in the art for an electrical test device that is hand held, and that is easy to use and which contains a minimal number of parts and is of low cost.